US4489850A - Closure member for pressure vessel - Google Patents

Abstract

A closure member for a pressure vessel having a ring assembly that has a radially expansible outside diameter and an inside diameter defining a central area, with the central area of the diameter greater than one-half the outside diameter, and with the ring assembly selectively engaging the pressure vessel between a locked position and an unlocked position.

Description

FIELD OF THE INVENTION

The present invention relates to closure members utilized in selectively sealing vessels capable of withstanding elevated pressures.

BACKGROUND OF THE INVENTION

Locking mechanisms for door assemblies have long been used on a wide variety of doors to a chamber and/or room that is desired to be isolated. Examples of various types of locking structures are shown in U.S. Pat. Nos. 1,269,572; 2,664,611; 4,114,933; and 4,342,207.

However, if the chamber and/or room that is to be secured requires an ability to maintain a greater pressure from within the chamber than exists outside the chamber, additional pressure related considerations must be taken into account. Such pressure vessel closure assemblies have long been known and include a wide variety of structures as shown in U.S. Pat. Nos. 2,010,200 and 3,258,151. Of the types of pressure closure assemblies for pressure vessels utilizing some type of annular or radially expanding element, some examples are shown in U.S. Pat. Nos. 2,196,895; 4,102,474 and 4,315,577. However, so far as known, all of the aforementioned pressure vessel closure members require centrally mounted and/or operated mechanisms for effectuating a radially expanding locking element. In some cases, as for example with U.S. Pat. No. 4,102,474, a central portion of a closure member is required to be maintained at a pressure in order to properly actuate particular elements thereof in order to accomplish the locking operation. In like fashion, U.S. Pat. No. 4,315,577 discloses a centrally mounted operator rotating in such a fashion that the locking elements are individually and independently moved outwardly based upon movement of a pin in a spiraling track.

Thus, so far as known, no pressure vessel closure member is available that provides an annular locking ring assembly having an unobstructed central area of a size greater than one-half the outside diameter of the closure member which permits a suitable viewport and/or other non-locking features to be incorporated with the pressure vessel closure member.

SUMMARY OF THE INVENTION

The present invention relates to a new and improved closure member for a pressure vessel having a ring assembly that has a radially expansible outside diameter and an inside diameter defining a central area, with the central area of the diameter greater than one-half the outside diameter, and with the ring assembly selectively engaging the pressure vessel between a locked position and an unlocked position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view, partly in section, of the closure member of the present invention;

FIG. 2 is a sectional view of the closure member of the present invention, as taken along thelines 2--2 of FIG. 1; and,

FIG. 3 is a plan view of one of the locking pawls of the present invention showing detailed angular considerations.

DESCRIPTION OF PREFERRED EMBODIMENT

The closure member of the present invention is designated generally with the letter C. It is adapted to be used with a pressure vessel V. The closure member C includes generally a ring assembly A having a central area X which may accommodate a viewport B. The ring assembly A includes an inner ring I, an outer ring O, a locking ring L, and locking pawls P which are selectively movable between a locked position wherein the ring assembly A lockably engages the pressure vessel V and an unlocked position wherein the ring assembly A does not lockably engage a pressure vessel V. Unless otherwise delineated, it is preferred that the components of the closure member C of the present invention be formed of suitable materials such as stainless steel, aluminum, and the like, capable of handling the extremes in pressures typically encountered in pressure vessels V of all types.

The closure member C of the present invention includes a ring assembly A. The ring assembly A includes an inner ring I which includes ring 10. The ring 10 is formed having an inner radial surface 1Oa, a beveled surface 10b, an outer radial surface 10c, an annular lip 10d, a radial surface 10e, abeveled surface 10f, an annular surface 10g, a radial surface 1Oh, an inner annular surface 10i, and abeveled surface 10j. Preferably asuitable opening 10k is formed in the inner ring 10 extending between inner radial surface 10a and outer radial surface 10c having asuitable countersunk portion 101 adjacent thereto.

The ring assembly A of the closure member C of the present invention further includes an outer ring O which includesouter ring 12. Theouter ring 12 is preferably formed having an outer radial surface 12a, an annular surface 12b, a radial detent 12c formed in the annular surface 12b, a radial surface 12d, an annular surface 12e, a radial surface 12f, an outer annular surface 12g, a radial detent 12h formed in the outer annular surface 12g, a beveled surface 12i, an innerradial surface 12j, anannular surface 12k, aradial surface 121, a beveled surface 12m, an innerannular surface 12n, and a beveled surface 12o. As discussed below, the outer ring O may alternatively be of a solid disc or plate-like configuration, with there being nosurfaces 12m, 12n.

The ring assembly A of the closure member C of the present invention further includes a locking ring L which includes locking ring 14. The locking ring 14 includes an outer radial surface 14a, an inner annular surface 14b formed having a radial detent 14c therein, an innerradial surface 14d formed having a plurality ofopenings 14e therein, an outerannular surface 14f and beveled surface 14g.

The ring assembly A of the closure member C further includes locking pawls P which are selectively movable between the locked position wherein the ring assembly A lockably engages the pressure vessel V and an unlocked position wherein the ring assembly A does not lockably engage the pressure vessel V. The locking pawls P includepawls 16 each of which is formed having an innerannular surface 16a, an outerannular surface 16b, a first end 16c, and asecond end 16d. Each of thepawls 16 further includes preferably a firstelongate slot 16e and a secondelongate slot 16f. Preferably the firstelongate slot 16e is formed having an inner point 16g in proximity to the innerannular surface 16a and having anouter point 16h in proximity to the outerannular surface 16b and the first end 16c. In like fashion, the secondelongate slot 16f is formed with theouter point 16j adjacent the outerannular surface 16b and with theinner point 16i in proximity to the innerannular surface 16a and thesecond end 16d. As such, each of theslots 16e, 16f of thepawls 16 are formed extending frominner points 16g, 16i, respectively in proximity to the innerannular surface 16a toouter points 16h, 16j, respectively, in proximity to the outerannular surface 16b. Preferably the innerannular surface 16a and outerannular surface 16b are concentric with one another for forming each of thepawls 16 of the locking pawls P in a substantially arcuate configuration. The locking pawls P further includes anouter plate surface 16k and aninner plate surface 161 as best seen in FIG. 2.

As illustrated in FIG. 1, it is preferred that there be six (6) arcuately shaped locking pawls P uniformly disposed equidistant about the perimeter of said ring assembly A, with each of the locking pawls P being of substantially 60° of the 360° perimeter of the ring assembly A. It will be appreciated that any number of locking pawls P may be uniformly disposed about the perimeter of the ring assembly A, as is desired. As best seen in FIGS. 1 and 3,slot 16e is formed at anangle 18 with respect to atangent 20 to a radial 22 intersecting thecentral axis 24 of the ring assembly A. In like fashion, the secondelongate slot 16f is formed at anangle 26 with respect to a tangent 28 to a radial 30 intersecting thecentral axis 24 of the ring assembly A. As such, for the reasons set forth hereinbelow, it is preferred that theangle 26 be smaller than that of theangle 18, on each of therespective pawls 16 of the locking pawls P.

Theelongate slots 16e, 16f preferably are substantially linear and of a non-arcuate configuration. Furthermore, as best seen in FIGS. 1 and 3,radials 32, 34 extending from thecentral axis 24 and running throughpoints 16h, 16g, respectively, of the firstelongate slot 16e form anangle 36 whileradials 38, 40 extending through thecentral axis 24 topoints 16j, 16i, respectively, of the secondelongate slot 16f form anangle 42 with respect to thecentral axis 24. As such, it is preferred that theangle 36 be greater than that ofangle 42 for the reasons set forth hereinbelow.

The ring assembly A of the present invention further includes dowel members D mounted with the locking ring L for engaging the locking pawls P as described below. The dowel members D may includedowels 44, 46 which are adapted to engageslots 16e, 16f, respectively. Furthermore,dowels 44, 46 of the dowel members D are adapted to be mounted with the locking ring L by suitable dowel bearing means 48, 50 which are adapted to be disposed inopenings 14e formed in the locking ring 14. Preferably, the dowel bearing means 48, 50 may be of any suitable type bearing capable of permitting rotation of thedowels 44, 46, as such engage theslots 16e, 16f of the locking pawls P. The dowel bearing means 48, 50 rotatably mounts thedowel members 44, 46, respectively with the locking ring L.

The ring assembly A of the closure member C of the present invention further includes bearing means B disposed between inner annular surface 14b of locking ring 14 and annular surface 12b ofouter ring 12 for rotationally securing the locking ring L with the outer ring O. The bearing means B includesbearings 52 which are preferably adapted to be mounted in the radial detents 12c, 14c of theouter ring 12 and locking ring 14, respectively. Asuitable fill port 54 of any desired design, for example, as shown in FIG. 2, permits access to the radial detents 12c, 14c for appropriate mounting of thebearings 52 therewithin. As such, thebearings 52 of the bearing means B act to secure the locking ring L with the outer ring O.

The closure member C of the present invention may further include aviewport 56 which is adapted to be fitted within the ring assembly A such that theviewport 56 is mountable in the central area X thereof. Preferably, theviewport 56 is formed having an outer surface 56a, an inner surface 56b, an annularbeveled surface 56c, annular surface 56d. While theviewport 56 may be of a suitable high strength plastic, glass or other transparent material, in the alternative theviewport 56 may be of any other suitable desirable material, whether or not such material may or may not permit viewing therethrough.

In the assembly of the closure member C of the present invention, it is contemplated that theviewport 56 be positioned such that the annularbeveled surface 56c abutts compatibly formed beveled surface 12m of theouter ring 12. Thereafter, the inner ring I is positioned with surfaces 10c, 10d, 10e thereof in mating engagement withsurfaces 12j, 12k, 12l, respectively, of theouter ring 12. Preferably asuitable member 58, which may be an O-ring or any other suitable sealing member, is disposed betweensurfaces 10f, 12l, and 56d to effect a sealing relation therebetween. Furthermore, a suitable sealingmember 60 is preferably disposed between the surface 1Oh of the inner ring I and the inner surface 56b of theviewport 56. Asuitable fastener 62 such as bolt 62a may be disposed withinopening 10k and countersunkportion 101, thereinto a suitably formed threadedopening 12p formed in theouter ring 12 for threadedly receiving thefastener 62 for securing the inner ring I with the outer ring O. It will be appreciated that a number offasteners 62 may be used for proper connection of the inner ring I with the outer ring O.

The locking pawls P are preferably disposed between the outer ring O and locking ring L such thatouter surface 16k ofpawl 16 is adapted to be disposed adjacent to innerradial surface 14d of locking ring 14 and radial surface 12d ofouter ring 12. Theinner surface 161 of thepawls 16 is adapted to be disposed adjacent to radial surface 12f ofouter ring 12. As such, the locking pawls P are uniformly movable between a retracted position and an expanded position. In the retracted position, the locking pawls P are of a minimum outside diameter (hence the ring assembly A is of a minimum diameter) such that the innerannular surface 16a of thepawls 16 is in immediate proximity to annular surface 12e of the outer ring and outerannular surface 16b is substantially aligned with outer annular surface 12g ofouter ring 12 and outerannular surface 14f of locking ring 14. In this retracted position, thedowels 44, 46 are in proximity toouter points 16h, 16j, ofslots 16e, 16f, respectively. When the locking pawls P are in the radially expanded position, the locking pawls P are in a maximum outside diameter configuration, as shown in FIG. 2 with the innerannular surface 16a no longer in proximity to the radial surface 12d and the outerannular surface 16b no longer aligned withannular surfaces 12g, 14f. In this expanded position, thedowels 44, 46 are in proximity toinner points 16g, 16i ofslots 16e, 16f, respectively. Movement of thedowels 44, 46 inslots 16e, 16f, respectively, effectuate the movement of the locking pawls P between the retracted position and the radially expanded position as shown in FIG. 2.Guide pads 80, preferably of a generally triangular configuration, act to guide the locking pawls P during movement thereof. Theguide pads 80 may be machined into or with the outer ring O adjacent surface 2f or alternatively, theguide pads 80 may be made of any type of friction reducing bearing materials, such as nylon, Teflon, or other desired materials and secured with the outer ring O by suitable fasteners 82 (which may include pins, bolts, screws, and like fasteners by way of example).

As noted hereinabove, the closure member C is adapted to be used with the pressure vessel V. The pressure vessel V includes avessel 64 preferably formed having an opening 64a. Preferably a suitable annular shoulder or groove 64b is formed in thevessel 64 adjacent to the opening 64a and is adapted to receive the locking pawls P when such are in the radially expanded position as shown in FIG. 2. The pressure vessel V may be of any type and for any intended use.

Thus, in the use of operation of the closure member C of the present invention, it is readily seen that the locking pawls P may move between a radially expanded position wherein the locking pawls P are received in an annular shoulder or groove 64b formed in thevessel 64, for securing the ring assembly A of the closure member C with the pressure vessel V. In achieving the locking operation, it will be appreciated that the locking ring L is easily rotated in the direction ofarrow 67 due to the bearing means B and dowel bearing means 48, 50 action between the outer ring O and locking pawls P, respectively. As the locking ring L is rotated in the direction ofarrow 67 with respect to the outer ring O, action between thedowels 44, 46 withslots 16e, 16f of the plurality of lockingpawls 16 results in a radially expanding locking pawl P which is engagable with the annular shoulder or groove 64b of thevessel 64. As a result, there is a substantially uniform radial engagement of the locking pawls P with the pressure vessel V as the locking ring L is rotated.

As noted above, it is preferred that theangle 18 be greater than theangle 26 in order to enhance the ease of rotation of the locking ring L as such is rotated from the unlocked position to a locked position. This is necessary because in order to move from a smaller circumferential diameter to that of a larger circumferential diameter, certain non-linearities must be accounted for. Specifically, it is necessary that there be an increase in radial force on theslot 16f in order to overcome increased friction force acting in the direction of force arrow 66b onsecond end 16d as compared to that of the first end 16c. Therefore by increasingangle 18 and decreasingangle 26, an increased radial force acting in the direction of arrow 66a in proximity to theslot 16f is generated to enhance the ability to overcome the resistive frictional forces typically encountered adjacent tosecond end 16d as thepawl 16 expands from a retracted to an expanded position. Furthermore, this angular difference betweenangles 18 and 26 is necessary due to the fact that thedowels 44, 46 of the dowel members D are on a fixed diameter which act on slots having a changing diameter as the locking pawls P respond to rotation of a locking ring L. This action also accounts for the fact thatangle 42 is smaller than that ofangle 36.

Alternatively, it is within the scope of the present invention thatangle 26 may be greater thanangle 18 and thatangle 42 may be greater thanangle 36 should it be desired that prealignment of thesecond end 16d of the locking pawls P be used for aligning the ring assembly A with pressure vessel V, by way of example. In this instance, theguide pads 80 may be of such a character to reduce the aforementioned friction-related problems.

While the closure member C of the present invention is illustrated in the drawings to move to a locked position with the pressue vessel V upon rotation in the direction ofarrow 67, it should be appreciated that by adjusting the orientation ofslots 16e, 16f of the locking pawls P, the direction of rotation to effectuate locking may be counter to that ofarrow 67, as desired.

Thus, the closure member C of the present invention includes a ring assembly A containing the entire locking mechanism in an annular member having a virtually unobstructed central area X therein which may receive suitable members such as aviewport 56, yet unencumbered with any locking structure. As such, the ring assembly A of the present invention has a central area X of a diameter greater than one-half of the outside diameter of the ring assembly A as defined by theannular surfaces 14f and 12g. In fact, experiments have shown that a central area X of the order of magnitude of substantially 75% of the total surface area of the ring assembly A may form the central area X of the ring assembly A. The central area X, as shown, includes aviewport 56; however, the central area X may include a solid element of a circular configuration such that the outer ring O is a substantially solid, flat disc or such may further include any non-door closure mechanisms of any type mountable with the outer ring O. By way of example, it is contemplated that the central area X may accommodate mounting of viewports, interconnections to and from the pressure vessel V, reduced thickness door sections for weight reduction considerations, and interconnections between various diameter pressure vessels, and the like with the pressure vessel V.

As a result, the closure member C of the present invention is virtually as efficient as snap-ring type locking closures, yet permits easy, releasable opening of the locking pawls P when the pressure vessel V is depressurized. On the other hand, when the slightest pressure exists within the pressure vessel V (greater than the pressure outside the pressure vessel V) this results in a substantial force acting between the locking pawls P in the radially expanded position working against the groove 64b in the pressure vesselV. Sealing member 68 insures a sealing relation between the outer ring O and the opening 64a of thepressure vessel 64.

It will be appreciated that on the event that the groove 64b is formed as a shoulder (not shown), there would be no portion of the pressure vessel V adjacentinner plate surface 161 of the locking pawl L (FIG. 2); and, the sealingmember 68 would be positioned between the locking ring L and vessel L yet on the opposite side of the locking pawl P (as viewed in FIG. 2) and would further require necessary seals between surfaces 12b, 14b.

Thus, the interior pressure within the pressure vessel V acts upon the substantial surface area of the locking pawls P against the annular groove 64b to prevent rotation of the locking ring R under such pressure conditions. Thus, the closure member C of the present invention provides a fail safe mechanism for preventing inadvertent opening of the closure member C when the pressure within the pressure vessel V is greater than that outside the pressure vessel V. Further, the locking ring R also insures that the locking pawls P either all engage the pressure vessel V or none engage the pressure vessel V, and thus eliminates the possibility of a partially secured door.

Thus, the closure member C of the present invention provides a new, improved mechanism for releasably securing a door member with a pressure vessel V.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made without departing from the spirit of the invention.

Claims (15)

I claim:

1. A closure member for a pressure vessel, comprising:

a ring assembly having an outside diameter and an inside diameter, said outside diameter being radially expansible and said inside diameter, defining a central area, said central area of a diameter greater than one-half said outside diameter;

said ring assembly selectively movable between a locked position wherein said ring assembly lockably engages the pressure vessel with said radially expansible outside diameter and an unlocked position wherein said ring assembly does not lockably engage the pressure vessel;

said ring assembly further includes:

a plurality of locking pawls maintained in a spaced relation to each other uniformly movable independently of each other between a retracted position wherein said locking pawls are of a minimum outside diameter permitting said unlocked position and an expanded position wherein said locking pawls are radially expanded into a maximum outside diameter in engagement with the pressure vessel to secure said ring assembly with the pressure vessel in said locked position;

each of said locking pawls having an inner annular surface, an outer annular surface, a first end, and a second end; and

each of said locking pawls having at least two elongate slots formed extending from an inner point proximate to said inner annular surface to an outer point proximate to said outer annualr surface, said first elongate slot adjacent said first end of said locking pawl at a different angle with respect to a tangent to a radial intersecting the central axis of said ring assembly than said second said elongate slot on said locking pawl.

2. The closure member of claim 1, further including:

a view port mountable in said central area.

3. The closure member of claim 1, wherein:

said first elongate slot formed with said outer point adjacent said first end in said outer annular surface;

said second elongate slot formed with said inner point adjacent said second end and said inner annular surface; and,

said angle of said first elongate slot is greater than said angle of said second elongate slot.

4. The closure member of claim 1, wherein:

said first elongate slot formed with said outer point adjacent said first end and said outer annular surface;

said second elongate slot formed with said inner point adjacent said second end and said inner annular surface; and

said angle of said first elongate slot is smaller than said angle of said second elongate slot.

5. The closure member of claim 1, wherein:

said first elongate slot formed with said outer point adjacent said first end and said outer annular surface;

said second elongate slot formed with said inner point adjacent said second end and said innder annular surface; and

said angle of said first elongate slot is equal to said angle of said second elongate slot.

6. The closure member of claim 1, wherein:

said elongate slot is substantially linear and non-arcuate.

7. The closure member of claim 1, wherein:

each of said locking pawls has said inner annular surface and said outer annular surface substantially concentric to one another for forming each of said locking pawls in a substantially arcuate configuration.

8. The closure member of claim 1, wherein said locking pawls further include:

six arcuately shaped locking pawls uniformly disposed equidistant about the perimeter of said ring assembly.

9. The closure member of claim 1, wherein said ring assembly includes:

an inner ring adapted to be removably mounted with the pressure vessel;

an outer ring mounted with said inner ring;

a locking ring disposed between said inner ring and said outer ring for rotational movement; and,

said locking pawls disposed between said locking ring and said inner ring.

10. The closure member of claim 9, wherein said ring assembly further includes:

dowel members mounted with said locking ring, each one of said dowel members engaging one of said slots in said locking pawls for independent movement of each said locking pawl in a spaced relation to an adjacent locking pawl between said retracted position and said expanded position upon rotation of said locking ring.

11. The closure member of claim 10, wherein said ring assembly further includes:

dowel bearing means for rotatively mounting said dowel members with said locking ring, said dowel bearing means mounted with said locking ring in bearing openings formed in said locking ring.

12. The closure member of claim 9, wherein said ring assembly further includes:

bearing means disposed between an inner annular surface of said locking ring and an annular surface of said outer ring for rotationally securing said locking ring with the said outer ring.

13. The closure member of claim 12, wherein said ring assembly further includes:

a fill port formed with said ring assembly for permitting said bearing means to be properly positioned between said outer ring and said locking ring.

14. The closure member of claim 1, wherein the pressure vessel is formed having an annular groove adjacent an opening thereof, wherein:

said locking pawls are adapted to be received in the annular groove of the pressure vessel upon movement of said locking pawls from said retracted position to said expanded position.

15. The closure member of claim 1, wherein:

said ring assembly bears the pressure loads of the pressure vessel when said ring assembly is in said locked position and pressure exists within the pressure vessel.

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